Social Choice Lecture 12 Carmen Pasca and John

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Social Choice Lecture 12 Carmen Pasca and John Hey

Social Choice Lecture 12 Carmen Pasca and John Hey

Voting Systems • Plan for today: to examine actual voting systems in use in

Voting Systems • Plan for today: to examine actual voting systems in use in Europe and to discuss their properties. • Electoral systems in Europe: We examine the rules and mechanisms used in democratic elections across the parliaments of Europe. • Elections lie at the heart of representative democracy, enacting citizens' rights to have a say in by whom they are governed. • The electoral process is the ultimate symbol and act of modern democratic societies.

Desirable features of voting systems 1 • All electoral systems seek to take account

Desirable features of voting systems 1 • All electoral systems seek to take account of at least some or all of the features on this and the following two slides; which of these are deemed most important tends to shape people's preference of electoral system. • Ensuring a representative parliament: parliaments should reflect the population that chose it, both in terms of political support, but also regionally and ethnically. • Making elections accessible and meaningful: Voters should feel that their taking part will make a difference to the result, or else they will increasingly refuse to participate, undermining the legitimacy of the results.

Desirable features of voting systems 2 • Facilitating efficient and stable government. The system

Desirable features of voting systems 2 • Facilitating efficient and stable government. The system should make it possible for the government of the day to enact legislation, run the economy and carry out the other tasks of government. The system should also be set up in such a way that it does not favour one party at the expense of the others. • Holding the government and representatives accountable for their actions. This is one of the corner stones of electoral systems. They must provide a check on the actions of individuals once elected, and provide an opportunity at regular intervals to remove those who the electorate feel are no longer suitable for office.

Desirable features of voting systems 3 • Promoting and respecting a parliamentary opposition. To

Desirable features of voting systems 3 • Promoting and respecting a parliamentary opposition. To be effective, governments also need to have an opposition to assess proposals critically, speak up for the interests of those not represented by the government, and provide reassurance to the electorate that there is always the possibility of changing governments at a later date. • On the next few slides we discuss the different types of voting systems that exist in practice.

Majoritarian systems • Majoritarian, or plurality, systems represent the oldest and simplest electoral system

Majoritarian systems • Majoritarian, or plurality, systems represent the oldest and simplest electoral system category, based on the principle that whichever candidate receives the most votes in a constituency is deemed elected. • The following three slides discuss three varieties of majority systems which operate on the basis of single-member constituencies.

'First-past-the-post' (FPTP) or simple majority • This is the most straightforward electoral system, and

'First-past-the-post' (FPTP) or simple majority • This is the most straightforward electoral system, and is found in the UK, USA, Canada and India. • To win, a candidate need only receive one more vote than any other candidate. Since a minimum threshold (i. e. a minimum level - usually a percentage - of the popular vote required for a party to be allowed to gain parliamentary representation) is rarely a part of this system and an absolute majority is not required, the winner may still win with a relatively small proportion of the vote.

Second Ballot Majority Runoff or absolute majority • This system requires a candidate to

Second Ballot Majority Runoff or absolute majority • This system requires a candidate to obtain one more vote than half the votes cast in order to be elected. If no candidate gets that many votes, a second round is held. • In this system, either a simple majority is sufficient in the second round, or a "run-off" election is held between the two candidates who received the most votes in the first round, also along absolute majority lines. France and the Ukraine both use variations of this system.

Alternative Vote • This system also seeks to ensure that a candidate is elected

Alternative Vote • This system also seeks to ensure that a candidate is elected by an absolute majority, but does so in a single round using Preferential Voting (i. e. expressing a rank order of preferences) instead of a two -stage system. Constituents vote for a single candidate but indicate, in declining order, their preferences for other candidates. If none of the candidate gets an absolute majority on the first count, the candidate who polled the fewest votes is eliminated, and his preferences are distributed among the remaining candidates. This is repeated until one of the candidates has an absolute majority. This is used in Australia and for the Irish presidential elections. • In the UK there will be a referendum in May to decide whether this system will be introduced there.

Properties of Majoritarian systems 1 • Majoritarian systems are simple. They do not require

Properties of Majoritarian systems 1 • Majoritarian systems are simple. They do not require complex mathematics to produce their results and they encourage transparency, since votes are easily translated into parliamentary seats. Many proportional systems, such as Single Transferable Vote, are unattractive in that they involve very lengthy and complex calculations. • The 'winner-takes-all' philosophy behind these systems focuses on producing a clear, strong and stable body of representatives and government, not on mirroring the makeup of the general population.

Properties of Majoritarian systems 2 • Because of the way that majoritarian systems disproportionately

Properties of Majoritarian systems 2 • Because of the way that majoritarian systems disproportionately reward large parties over small parties, the leading party is rarely required to build a coalition to create a government. • A one-party government (which, one should remember, is already a complex coalition of interests) is therefore free of the problems that can emerge from being involved in a coalition which might make it weak: government is immediately broadly united; policy need not be diluted as it might in a coalition where a partner party may demand policy concessions; ministerial portfolios can be distributed without fear of party political battles or major policy cleavages (although other battles will still rage); the identity and message of a party in government need not be confused, or aggravated, by its close association with another party.

Properties of Majoritarian systems 3 • Just as a majoritarian system tends to create

Properties of Majoritarian systems 3 • Just as a majoritarian system tends to create strong government, it also tends to lead to a strong alternative party, such as in the UK and the USA. • This creates a dynamic political arena where government needs to work hard because there is always a viable and strong alternative which the public can chose to replace them with • Smaller parties are not effectively represented in majoritarian systems can be seen to have some advantages. They encourage minority groups to integrate into the larger parties, which is desirable both for the minority group (which can gain the political support for some or all of its concerns) and the large group (which gains the electoral support of the minority).

Properties of Majoritarian systems 4 • Different groups are brought together by political need

Properties of Majoritarian systems 4 • Different groups are brought together by political need which encourages cooperation and the creation of parties with 'broad church' appeal, rather than division by electoral systems which may only serve to highlight differences and keep minorities at a distance. It can also serve to discourage extremist minority parties from gaining parliamentary representation, • Individual citizens feel that they are part of the democratic process through a single representative, who is there to help with individual or community casework. The election of representatives by a proportional system in a multi-member constituency (which may even be the entire country) would not determine this link.

Properties of Majoritarian systems 5 • Single-member constituencies which operate in majoritarian systems also

Properties of Majoritarian systems 5 • Single-member constituencies which operate in majoritarian systems also encourage the linkage of an elected representative to a particular geographic area and the residents of that area, who become his or her constituents. This link encourages those elected to prioritise serving their constituents above satisfying the party hierarchy, since their re-election will depend entirely on those same people. • This link is particularly important in the UK, where MPs have always been viewed as representatives of a specific area, not of the UK as a whole.

Proportional Systems 1 • While majoritarian systems provide the oldest model for electoral systems,

Proportional Systems 1 • While majoritarian systems provide the oldest model for electoral systems, proportional representation (PR) systems are currently the most widely used in Europe. Its focus is on the creation of a parliamentary chamber which accurately reflects the diverse make-up of an electorate. The two main PR system categories are Party List and Single Transferable Vote. Both of these carry a range of considerations in creating representative parliaments.

Proportional Systems 2 • The size of the constituency (also refered to as 'district

Proportional Systems 2 • The size of the constituency (also refered to as 'district magnitude') is important since it can affect how 'accurate' the results reflect a general electorate. 'Full PR' considers the whole country as a single constituency, with seats allocated on a pro rata basis according to the number of votes cast. This is considered to yield the most 'pure' form of PR. 'Limited PR' sees elections taking place in several constituencies, and is considered to not produce as accurate a snapshot of the population, since the greater the number of constituencies (and hence the fewer the number of seats available per constituency), the harder it is to ensure complete proportionality.

Proportional Systems 3 • Many systems used include a threshold. • This aims to

Proportional Systems 3 • Many systems used include a threshold. • This aims to reduce the extent to which proportionality is taken. By putting in place a minimum level of national support required for a political party to be allowed to gain parliamentary representation, it limits the ability for very small parties to gain representation. It is understood that the electoral threshold had its origin in inter-war Germany, as a result of the Weimar Republic's concern with extremist groups. Some thresholds are nominal, others are so large that it challenges the basic idea behind using a PR system.

Proportional Systems 4 • In some countries, political parties not reaching the thresholds and

Proportional Systems 4 • In some countries, political parties not reaching the thresholds and getting no seats can potentially waste millions of votes. Another requirement which some countries (many in central and eastern Europe) also have in place is a minimum quorum level, which demands that for an election to be deemed valid and fully representative the turnout must meet or exceed a percentage of the electorate.

Party List system 1 • A Party List system presents multi-member constituency electorates with

Party List system 1 • A Party List system presents multi-member constituency electorates with political parties putting forward slates or lists of candidates. • It represents the principal PR system in operation, although there are many variations of it, based on constituency size (as covered above), thresholds and quorums (also examined above), rules about whether the electorate can have preferences for individuals on party lists, whether the Greatest Remainder or Highest Average systems are used and which formulas are used within them.

Party List system 2 • Before looking at the Greatest Remainder and Highest Average

Party List system 2 • Before looking at the Greatest Remainder and Highest Average systems, one must cover perhaps the most important variant in the Party List system: the ability of the voter to influence the party list. The ability of the voter to influence the party lists acknowledges that voters will often have preferences for individual candidates within party lists and that they might also wish to satisfy those preferences regardless of what the party hierarchies have put in front of them. The extent to which a voter can have choice in a Party List PR system is determined by one of the following variations. Preferential Voting allows voters to decide their own order of preference, different from that indicated by the party. The voters may only, however, vote for one list. Vote-Splitting allows voters to select candidates from competing lists, and thus draw up their own list. The commonest used variation is the Closed List system, where the electorate are simply allowed to vote for one party list, not an individual. It is up to the party to decide who should get the chance to fill the seats given to them (usually determined well in advance with the candidates placed in order of priority).

Preferential Voting • Preferential Voting allows voters to decide their own order of preference,

Preferential Voting • Preferential Voting allows voters to decide their own order of preference, different from that indicated by the party. • The voters may only, however, vote for one list. Vote-Splitting allows voters to select candidates from competing lists, and thus draw up their own list. • The commonest used variation is the Closed List system, where the electorate are simply allowed to vote for one party list, not an individual. It is up to the party to decide who should get the chance to fill the seats given to them (usually determined well in advance with the candidates placed in order of priority).

Proportional Representation • The experience of PR has been that it has increased the

Proportional Representation • The experience of PR has been that it has increased the number of women in parliaments. Some political parties have taken affirmative action and drawn up official targets for the proportion of women and those from ethnic minorities on their party lists. Defenders of such targets argue that although artificial, its aim is to temporarily speed-up change to the status quo, which can often only be done by such targets in closed PR systems. • PR tends not to result in one party having an absolute majority of the votes, thus making coalition government the norm. This leads, in theory at least, to a more consensual and inclusive style of government.

Mixed Systems 1 • There a range of systems which try to strike a

Mixed Systems 1 • There a range of systems which try to strike a balance between majoritarian and proportional representation systems, and are generally (if rather untidily) categorised as Mixed Systems. • These can broadly be divided into those which try to bring together elements of majoritarian and proportional systems to try and come up with a seat-distributing mechanism incorporating the best of both world (but end up tending to lean more towards one system or the other), and systems where both majoritarian and proportional mechanisms are used in different stages.

Mixed Systems 2 • Cumulative or Block Vote. • Voters have a number of

Mixed Systems 2 • Cumulative or Block Vote. • Voters have a number of votes equal to the number of seats available and are free to distribute them as they please among all the candidates, even to the extent that one candidate can receive all the votes of one voter, or conversely, where the voter can give each candidate one vote. Seats are distributed among candidates polling the most votes. A variation of this is Party Block Vote, where voters are only allowed to vote once for one entire party list, which results in the entire list of candidates of the winning party list taking all the seats in a multi-member constituency.

Mixed Systems 3 • Limited Voting. Used in multi-member constituencies, voters may vote for

Mixed Systems 3 • Limited Voting. Used in multi-member constituencies, voters may vote for several candidates on the ballot paper, but always fewer than the number of seats to be filled. Candidates polling the most votes are elected. It was used in some UK constituencies in the late 19 th century. • Single Non-Transferable Vote. Under this system, there are several seats to be allocated in each constituency. However, each voter may only vote for a single candidate, with those candidates who gain the most votes being elected. • These systems, however, use separate majoritarian and proportional mechanisms for different constituencies • Additional Member (or Parallel) system. A proportion of seats are distributed using a majoritarian method, while the remaining seats are allocated using a PR system, usually on a regional or nationwide basis. The Russian Duma, for example, has seats elected by a majority vote in single-member constituencies, as well as by PR nationally. Japan is also a user of this system.

Mixed Systems 4 • Mixed Member Proportional system (MMP). This system works very similarly

Mixed Systems 4 • Mixed Member Proportional system (MMP). This system works very similarly to Additional Member, in that it incorporates majority voting for one portion of the seats and Party List PR for the other. However, "under MMP the list PR seats compensate for any disproportionality produces by the [ majoritarian system-elected] district seat results. For example, if one party wins 10% of the national votes but no district seats, then they would be awarded enough seats from the PR lists to bring their representation up to approximately 10% of the parliament". This 'compensating' mechanism system is used in Germany, Hungary and New Zealand, and is seen as particularly benefitial in its ability to keep local constituency representation while also awarding smaller parties their fair share of the popular vote.

Systems for National Elections in EU states 1 • The systems used for parliamentary

Systems for National Elections in EU states 1 • The systems used for parliamentary elections in the member states of the European Union present a varied picture, each products of different political circumstances and traditions. Bicameral, unicameral, majoritarian, proportional, and mixed systems are all well represented in the EU, displaying a diversity which is often augmented by certain aspects of the electoral law not concerning the vote-distribution mechanisms. • Compulsory voting rules in Belgium and Greece, for example, sit alongside the less demanding requirements of other Member States.

Systems for National Elections in EU states 2 • In the bicameral systems, the

Systems for National Elections in EU states 2 • In the bicameral systems, the Lower House is the most important, the result there determining the make-up of the government. A wide range of systems are in use for parliamentary elections, although proportional systems dominate. The UK uses the FPTP system in single-member constituencies. France also has single-member constituencies, but uses the two-stage Second Ballot Majority Runoff system, where an absolute majority is required to gain a seat. Spain, and Italy use the Additional Member system, while Germany uses the Mixed Member Proportional system. Finland's system is principally PR, but the representative for Finland is chosen by simple majority.

Systems for National Elections in EU states 3 • Most of the Upper Houses

Systems for National Elections in EU states 3 • Most of the Upper Houses are chosen by appointment or indirect election, while three - Belgium, Spain and Italy - have directly elected elements. • Belgium uses the same proportionality-based voting system as for the Lower House, but the representatives are chosen along the lines of the regions and language communities. • Italy uses a mixed system for the Upper House, most seats being filled by simple majority voting, the rest by proportionality. • Spain's Upper House has most places filled by simple majority voting, but about a sixth of seats are indirectly chosen by regional assemblies.

Systems for National Elections in EU states 4 • The indirectly appointed upper chambers

Systems for National Elections in EU states 4 • The indirectly appointed upper chambers have a variety of different methods for choosing members. • In four of the countries - Germany, Austria, Holland Spain - the Upper House is made up of members of regional or local assemblies. In France, the Senate is made up of people chosen by local electoral colleges. • In Ireland, appointments to the Upper House are made in part by the Prime Minister and by indirect elections by some universities, county councils, panels representing different interests in society or the outgoing House. In the United Kingdom, there are four groups of members: hereditary peers (aristocracy), life peers, Law lords, and certain bishops. The government recently started a two-stage reform of the House of Lords, removing the right to sit for all but 92 hereditary peers in an "interim" house. Stage two will produce a final dispensation, following the publication of the report from a Royal Commission to consider the composition, roles and functions of the second chamber.

Summary of voting systems 1 • Absolute Majority: More than half the total number

Summary of voting systems 1 • Absolute Majority: More than half the total number of votes cast. For the Absolute Majority system, see Second Ballot Majority Runoff. • Additional Member (or Parallel) system: Mixed electoral system where a proportion of seats are distributed using a majoritarian system, and where others are distributed on a proportional basis. • Alternative Vote system: Preferential absolute majority system, usually used in single-member constituencies, where voters number candidates in order of preference. If there is no outright winner, the least favoured candidate is eliminated and his second preferences are redistributed. This continues until someone gets over 50% of the vote.

Summary of voting systems 2 • Closed List: A list of candidates (in rank

Summary of voting systems 2 • Closed List: A list of candidates (in rank order of priority to be given seats) drawn-up for elections taking place by a form of Party List, which may not be adjusted by the voter. • Constituency: A geographical area into which a country is divided for elections. Can be a 'single-member constituency' where only one parliamentary seat is being contested, or a 'multi-member constituency' where more than one seat is being contested.

Summary of voting systems 3 • Cumulative (or Block) Vote: A majoritarian system for

Summary of voting systems 3 • Cumulative (or Block) Vote: A majoritarian system for use in multi-member constituencies where voters have a number of votes equal to the number of candidates standing and are free to distribute them as they please. Seats are filled according to who receives the most votes. • D'Hondt Quota: The most common divisor used in the Highest Average Party PR system, it operates the following dividers: 1, 2 , 3, 4, etc. • Droop Quota: Used for allocating seats in both the Greatest Remainder Party List and the Single Tranferable Vote systems, it

Summary of voting systems 4 • Elimination: In Alternative Vote and STV systems, it

Summary of voting systems 4 • Elimination: In Alternative Vote and STV systems, it occurs when candidates have too few votes to remain in a contest. • 'First-Past-The-Post' (FTPT)(or Simple majority) system: Candidate with the largest number of votes wins, regardless of whether he or she has an absolute majority. • Greatest (or Largest) Remainder system: A Party List PR system which uses a type of formula (e. g. Hare, Imperiali, etc) to devise a quota of the votes necessary for a party to secure a seat. Once all seats have been distributed according to the quota, remaining votes which do not reach the quota are counted to distribute any remaining seats to those with the most votes left-over.

Summary of voting systems 5 • Hare (or Simple) Quota: A variety of the

Summary of voting systems 5 • Hare (or Simple) Quota: A variety of the Greatest Remainder Party List PR system, it is a quota calculated as 'votes divided by seats'. • Highest Average system: A Party List PR system which distributes seats according to parties which have the highest averages after being divided by a particular formula (e. g. d'Hondt, Sainte-Lague system, etc). • Imperiali Quota: The quota under this system is reached by dividing the total number of votes cast by the number of seats to be filled, increased by two. • Limited Vote: Used in multi-member constituencies, voters may vote for several candidates on the ballot paper, but always fewer than the number of seats to be filled. Candidates polling the most votes are elected.

Summary of voting systems 6 • Majoritarian systems: Generic term for systems where seat(s)

Summary of voting systems 6 • Majoritarian systems: Generic term for systems where seat(s) are distributed according to whichever candidate(s) get the most individual votes. • Mixed Member Proportional system (MMP): This system works very similarly to Additional Member, in that it incorporates majority voting for one portion of the seats and Party List PR for the other. However, it differs in its ability to award seats through PR to overcompensate for parties which attracted a good share of the popular vote in the majoritarian elections, but failed to make any gains. • Mixed systems: Generic term for single electoral systems which are either composed of elements of both majoritarian and proportional systems or those which include separate majoritarian/proportional procedures, such as the Additional Member system. • Parallel system: See Additional Member system.

Summary of voting systems 7 • Party Block Vote: Voters are only allowed to

Summary of voting systems 7 • Party Block Vote: Voters are only allowed to vote once for one entire party list, resulting in the entire list of candidates of the winning party list taking all the seats in a multi-member constituency. • Party List system: The principal PR system, operated by either Greatest Remainder or Highest Average formula, it is an election in a multi-member constituency where all candidates are placed on political party 'lists'. Depending on the variety, an electorate may only be able to vote according to Closed List rules, may be able to partake in Preferential Voting, or could even pick and choose candidates from across the lists, as allowed by Vote-Splitting.

Summary of voting systems 8 • Preferential Voting: Party List PR rule variant which

Summary of voting systems 8 • Preferential Voting: Party List PR rule variant which enables voters, once they have voted for one party list, to choose their prefered ranking of candidates. • Proportional Representation (PR): Generic term for systems which seek to ensure that the results of elections are as proportional as possible to the make-up of an electorate. Party List systems and STV are varieties of PR.

Summary of voting systems 9 • Quorum: a minimum level - usually a percentage

Summary of voting systems 9 • Quorum: a minimum level - usually a percentage - of the full electorate required to vote to validate the results of an election. (i. e. If only 29% of an electorate voted in an election requiring a 35% quorum, the results would be deemed invalid due to the low level of voter participation). • Single Non-Transferable Vote: A mixed system for use in multi-member constituencies, where voters only have one vote. Those who receive the most votes win. • Single Transferable Vote (STV): Main alternative PR system to Party List, a candidate is elected as soon as he reaches the a quota calculated by the Droop quota. Additional votes are redistributed to other candidates on the basis of second choices. The same operation is carried out in the case of the candidate who polled fewest votes, who is eliminated. If there are still seats to be filled after the second count, the process continues. • Threshold: A minimum condition for securing representation. This divide limits purely proportional results by distributing seats only to parties with … • Vote-Splitting: This allows voters to select candidates from competing lists in a Party List PR system, and thus draw up their own list of candidates.

Conclusions • There is no perfect voting system (but we knew that from Arrow!).

Conclusions • There is no perfect voting system (but we knew that from Arrow!). • There is a big literature pointing out the pros and cons of the various systems. • Different countries have different systems. • Why? • Partly historical and partly cultural.